A-Z Health Topics

Thyroid Disorders in Pregnancy

Definition

The thyroid is a butterfly-shaped gland located in the front of the neck. It produces hormones that control metabolism. Pregnancy hormones can affect thyroid hormones. Untreated thyroid disorders in pregnancy increase the risk of pregnancy complications. It may cause harm to the developing fetus. There are two types of thyroid disorders:

Causes

Hypothyroidism

Hashimotos disease is the most common cause of
hypothyroidism. The immune system attacks the thyroid gland. Other causes of hypothyroidism in pregnancy include:

Inadequate treatment of pre-existing hypothyroidism

Overtreatment of hyperthyroidism

Hyperthyroidism

Graves disease is characterized by overactivity of the thyroid. It is the most common cause of
hyperthyroidism. Another cause of hyperthyroidism in pregnancy is very high levels of human chorionic gonadotropin (hCG).
However, cases of high hCG can resolve on their own.

Diagnosis

Your doctor will ask about your symptoms and medical history. A physical exam will be done.

Your doctor will test your thryoid hormone levels and other blood tests. Imaging of the thyroid may also be done. You may be referred to a doctor who specializes in hormone disorders.

Treatment

Hypothyroidism

To treat hypothyroidism, your doctor will prescribe medication
to replace the hormone your thyroid is not producing enough of.

Hyperthyroidism

Mild hyperthyroidism during pregnancy is often monitored closely without therapy. In some cases, you may need to take medication. If antithyroid medications do not work,
surgical removal
of your thyroid gland may be done. It is rarely recommended during pregnancy. Treatment with radioiodine destroys the thyroid gland. It is not done during pregnancy because of risk to the fetus.

Hashimoto’s disease. American Academy of Family Physicians Family Doctor website. Available at:
http://familydoctor.org/familydoctor/en/diseases-conditions/hashimotos-disease.html. Updated November 2010. Accessed June 10, 2013.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.